Dairy process



PB 32 w49 H. c. HoRNEMAN r-:r m 2,466,896

DAIRY PROCESS Original Filed Dec. 6, .1940

Patented Apr. l2, 1949 DAIRY PROCESS Herman C. Horneman, Danville, Ralph V. Hussong, Urbana, Sidney N. Quam, Danville, Ill., and Bernard W. Hammer, Sarasota, Fla., assignors to Sugar Creek Creamery4 Company, Danville, Ill., a corporation of Delaware, and Cherry-Burrell Corporation, Chicago, Ill;, a corporation of Delaware, as joint owners Original application December 6, 1940, Serial No. 368,750. Divided and this application April 12, 1947, Serial No. 741,090

12 Claims.

The present invention relates to processes for handling cream and producing butter. More particularly, this invention relates to improvements in a process for producing a dairy product having a high milk fat concentration and for producing butter from such an improved dairy product.

Prior processes used in the commercial manufacture of butter are, generally speaking, in essence `the same and are commonly known as batch processes. Such batch processes generally employ a churn for churning cream having a butterfat content of approximately thirty percent in the production of butter and buttermilk. With the exception of the preliminary cream treatments and with the exception of minor mechanical or apparatus changes, there has not been an important or revolutionary improvement in methods adapted for the commercial manufacture of butter, for many years.

This application isa division of our parent application Serial No. 368,750, filed December 6, 1940, and entitled Butter process, now Patent No. 2,423,834.

In the art of manufacturing butter, it has long been recognized that a need existed for improvements in processes for. producing butter. Prior investigators have suggested various modications of such old processes. Such suggested modifications have, however, generally failed. One of such suggested modifications proposed the use of a process for producing butter from a plastic or super-cream, containing in the neighborhood of slxty-iive percent (65%) milk fat. That particular modification of the old processes of manufacturing butter, likeunto other modiiications, included a modication contemplating the use of a converter or agitating means for the reversal of the phase of the milk fat in the cream, i. e., changing the dispersed phase of the milk fat, which is present in the cream, to a continuous phase. Modifications of the mentioned type in the accepted processes for the manufacture of butter which call for 'the reversal of the phase of the milk fat in a high fat cream product have not been found to be satisfactory, and as a result have not proved successful up to the present time. a

It is an object of the present invention to provide an improved process for producing milk fat concentrate.

Itis also an object of the' present invention to provide an improved process for producing butter. It is a further object of the present invention to provide a continuous process for the production of butter having improved qualities and characteristics.

It is a still further object oi the present in vention to provide commercially satisfactory processes for producing milk fat concentrate and butter ,free from the common objectionable characteristics and aspects associated with butter made by prior usable butter manufacturing processes.

Other objects and advantages of the present invention will be more apparent as the following description is considered.

We have discovered commercially satisfactory processes for producing milk fat concentrate and butter having the generally desired physical and chemical characteristics and aspects. The improved processes, in general, include the steps of introducing cream into a zone or chamber wherein the cream is subjected to sub-atmospheric pressure and wherein the cream is subjected to the direct action of steam while under such a reduced pressure, concentration of the -milk fat in the cream being processed by subjection of 25 the cream, while at a temperature above the melting point of the milk fat content thereof, to a centrifuging action, separation of the concentrated milk fat, which has been thus obtained and in which the fat portion thereof is in the continuous phase, from other constituents of the cream, and thereafter working said concentrated milk fat product to produce butter having the desired physical and chemical characteristics and aspects. The cream used in the above process may or may not, as appears desirable, be pretreated, although the use of a high quality, pasteurized creamis generally preferred. 4

For a more complete understanding of the nature and scope of the invention, reference may be made to the following detailed description thereof,to be read in connectionwith and with reference'to the accompanying drawing, wherein the single iigure is a flow sheet diagrammatically illustrating steps or sequences of operations contemplated by this invention. l

As illustrated in the drawing, cream having a milk fat concentration of approximately 30 percent to 40 percent is warmed in a prewarming vat l to a temperature of approximately F. to F. the cream to be used in the process is desired, the neutralization may be carried out, for example, in the prewarniing vat I, in accordance with the general practice commonly followed in the buttermaking art.) From the vat I, the cream (In the event that neutralization of i 3 is pumped by pump 2 through conduit 3 into an through illter 4. Steam under a pressure of approximately 90 to 100 pounds per squareinch is introduced into the conduit 3 at station 5 from a steam supply line 5. The mixture of the cream and steam in the conduit 3 raises the temperature of the cream suiciently so that the cream enters the filter 4 at a temperature of approximately 135 F. From the filter 4, cream ilows through conduit, Sinto a flash pasteurizer 1, which may, for example, be of the well recognized and commonly known Jensen type. Steam is also introduced into a conduit 6 at station 8 from the steam supply line 8. The mixture of the filtered cream with the steam in the conduit 8 raises the temperature of the cream sufilciently so that the cream enters thev bottom of the pasteurizer from the conduit 8 at a temperature of approximately 150 F. to 160 F. The cream under generally' accepted operating conditions remains in the pasteurizer 'I for a period of time of approximately 10 to 15 seconds, during which period of time the cream being pasteurized is heated to a temperature of approximate1yl90 F. to 194 F. Such additional heating of the cream in the pasteurizer 1 may be accomplished,

for example, by the use of steam for indirectly heating the cream in the manner common in the art of the well-known Jensen type of pasteurizer. The pasteurized cream flows from the pasteurizer 'I through conduit 9 to a supply tank III, from which,.in turn, it flows through conduit Il I to a zone of sub-atmospheric or reduced pressure for vacuum-steam treatment.

The cream having a temperature of approximately 175 F. to 190 F. is drawn through the conduit Il into the vacuum pasteurizer I2, in which exists the zone of sub-atmospheric or reduced pressure and which vacuum pasteurizer may, if desired, be of the type described in more detail in the United States Patent No. 2,022,420. The pressure existing within the vacuum pasteurizer or chamber I2 is of a sub-atmospheric or reduced nature and preferably is maintained at a reduced pressure of approximately 25 to 26 inches of mercury, as a result of which the maximumtemperature within the chamber I2 will be approximately 130 F. to 135 F. Steam under a pressure of approximately 90 pounds per square inch is introduced into the bottom of the vacuum pasteurizer or chamber I2 through the steam pipes I3, as illustrated in the drawing, whereby the steam comes into direct contact with the cream within the chamber I2 while the cream is under a reduced or sub-atmospheric pressure. The desired and preferred pressures and temperatures are readily maintained in the chamber I2 by withdrawing vapor or volatile gases containing objectionable ilavoring materials through the passage I4 by means of any conventional apparatus, such as a vacuum pump (not shown).

The treated cream, which has sniered practically no net loss or gain in its moisture content, collects in the lower portion of the chamber I2, from which it is drawn by pump I5 and forced through conduit i6 to the centrifuging separator Il. The cream within the separator I1 is in genv eral terminology of a temperature of approxifat is separated from the proteins, skim milk,

etc., and is discharged therefrom in a mixture in 4 which the milk fat portion thereof is in the continuous phase and in a liquid form. The mixture containing the milk fat is expelled from the separator at the station I 3 and contains approxil mately 80 percent to 98 percent milk fat, depending upon the extent of the above-mentioned centrifuging action. The major portion of such milk fat is in the continuous phase, and is next passed from station I3 through conduit I9 to the vat 20. From the vat 2U the milk fat product, with the milk fat still in a liquid state and in the continuy ous phase, is pumped by pump 2l through the conduits 22 and 23 to the mixing chamber 24. A controlled aqueous solution of salt, starter fiavors, etc., may be pumped from the vat 25 by the pump 2G through the conduits 2T and 23 into the mixing chamber 24, wherein such aqueous solution may then be mixed with the fat product supplied to the chamber 24 from the vat 20. The resulting mixture, containing at least 80 percent milk fat, is then conducted from the mixing chamber 24 through conduit 28 to a cooling and stabilizing unit 29, wherein the temperature of the mixture is reduced to a temperature of ap- 25 proximately 40 F. to 60 F. The cooled and stabilized mixture is conducted from the cooler and stabilizer 23 through the conduit 30 into the tempering unit 3|, wherein the desired texture is imparted or developed in the butter thus produced. The tempered product is forced from the tempering unit 3| and conducted through the conduit 32 to a suitable packaging machine (not shown).

It will be understood that the above repre- 35 sentative detailed description of the preferred method of practicing the improved process is merely illustrative and that the present invention is not limited thereto. The pre-treatments, including iiltering and pasteurizing the cream, may be modiiled or eliminated in Whole or in part, as

desired. Pasteurization of the cream, for example, may be performed entirely by mixing steam and cream. The working of the milk fat mixture after it is discharged from the separator, including mixing the mixture with water and with salt or with brine if salted butter is desired, etc., as well as the cooling and tempering, oommonly referred to in the art of buttermaking as aging, may also be modiied if desired. Optimum conditions which may vary with the particular type of milk fat present in the cream, which in turn varies with the seasons of the year and the respective localities from which the cream is secured and the feed which has been consumed by the cows from which the milk is secured, may readily be determined by conducting conventional types of tests, commonly practiced in the art of butter manufacture.

The temperatures and pressures in the vacuum pasteurizer I2 and in the separator II, referred `to in the preceding detailed description of the improved process, of necessity represent one set of preferred conditions for the practice of the improved process. The mentioned illustrative temperatures and pressures, however, may-also be modified as desired and necessary and optimum conditions, including the necessary time of treatment within the vacuum pasteurizer (e. g. 5 to 30 minutes), should be varied on the basis of the particular type of cream undergoing treatment.

The change in the cream during the vacuumsteam treatment is not fully understood. Our investigations indicate that subjecting the cream to sub-atmospheric pressure produced an expansion of the cream, and that the action of the aeoaseo steam (e. g. steam under a high pressure of 90 to 100 pounds per square inch immediately ahead of the steam nozzle), coming into direct contact with the cream which is in the expanded state, modifies the milk fat globules so that they separate into the continuous phase when later subjected to the centrifuging action in the separator. Our investigations also indicate that the best results are obtained when the cream entering the zone of sub-atmospheric pressure is preheated to a temperature greater than the temperature of saturated steam at a reduced or subatmospheric pressure within the mentioned zone. The fact that the fat is obtained in the continuous phase indicates that the complex proteinfat-hull or membrane surrounding the milk fat globule is modified physically or chemically or both by the combined vacuum and steam treatment in chamber I2. It will be understood, however, that the present invention is not limited by theoretical explanations.

The addition of a controlled amount of water to the concentrated milk fat enables the securing of a more uniform or ner dispersion of water in a water-in-fat emulsion, resulting in an improved texture in the butter made from such emulsion. The amount of water added varies with the percentage of milk fat in the concentrated milk fat emulsion, which concentrated milk fat emulsion preferably contains 85 percent to 95 percent fat. The amount of water thus added to the milk fat emulsion is controlled so that the final butter product contains at least 80 percent milk fat.

The aspect of the present invention pertaining to the fine dispersion of water or brine in the milk fat emulsion and the low protein content of the emulsion, as well as the removal of substantially all of the original water and water soluble materials from the milk fat which is to be used for the manufacture of butter, enables the advantageous use of the invention in the production of a stable butter. A substantial proportion of nitrogenous material-one of the bacterial foods in butter-is separated from the milk fat in the centrifugal separator.

As previously mentioned, the raw milk or cream as contemplated by this invention containsonly approximately 35 percent milk fat. The advantages obtained by replacing the original non-fat materials of the cream with controlled water starter mixtures free from undesired contamination will be obvious to those skilled in the art. An additional advantage of the present invention resides in the elimination of churning commonly carried out today, for the most part, in bacteria-contaminated wooden churns.

It would be obvious to those skilled in the art that the milk fat concentrate of the present invention is particularly adaptable for use as an intermediate in the preparation or manufacture of butter, in which the quality and composition of the concentrate may be accurately controlled.

It will also be obvious to those skilled in the art that the mentioned milk fat concentrate is also adaptable for use in the manufacture of cheese, ice cream, frozen desserts, confections,

l baked goods and the like.

It will be understood that the present invention is not limited to the illustrative process herein described. All modifications coming within the scope of the present invention are intended to be covered in the appended claims.

In the specifications and claims, the term starter refers to starter cultures. Such cultures are well known in the art of buttermaklng and serve as means for avoring the manufactured butter. the term cream is used with the thought that it is to be given the ordinary or conventional meaning and is used to identify a product in which the milk fat is in the dispersed phase, i. e., the milk fat dispersed as an emulsion in a continuous phase of non-fat milk liquids. Cream products differ materially from the concentrated fat or fat concentrate of they present invention, in\which fat concentrate the milk fat is present in the continuous phase.

The invention is hereby claimed as follows:

1. A process for treating a liquid dairy product containing milk fat in the dispersed phase and milk serum in the continuous phase to reverse the normal emulsion phase relation, comprising flowing the dairy product through means for applying mechanical stresses thereto whereby the milk serum phase is disrupted and dispersed and the normally dispersed milk fat phase is merged in the continuous phase containing the dispersed milk serum as a serum in fat mixture.

2. A process for treating a liquid dairy product containing milk fat in the dispersed phase and milkserum in the continuous phase to reverse the normal emulsion phase'relation, comprising flowing the dairy product through means for applying mechanical stresses thereto whereby the milk `serum phase is disrupted and dispersed and the normally dispersed milk fat phase is merged into a continuous phase containing the dispersed milk serum in an unstable readily separable serum in fat mixture, and then separating the mixture to produce a portion having a high milk Y fat concentration.

.3. A process for treating a flowing stream of heated liquid cream to facilitate the separation 4,0 of a portion thereof having a high milk fat coni heated liquid dairy product containing milk fat in the dispersed phase to facilitate the separation of a portion thereof having a high milk fat concentration, comprising subjecting the dairy product to forces effective to break the normal milk fat in milk serum emulsion and produce a mixture of milk serum dispersed in milk fat wherein substantially alll of the milk fat and milk serum portions are in unstable readily separable relation.

5. A process for treating a dairy product which has previously been heated to a milk fat melting temperature and which contains milk fat in the dispersed phasel and contains milk serum in the continuous phase to disrupt its normal phase relation, comprising flowing a stream of the heated dairy product between closely spaced surfaces wherein the relative motion between the dairyproduct and the surfaces is of relatively high velocity, whereby the normally continuous milk serum phase is disrupted and dispersed and the normally dispersed milk fai; phase is merged into a. continuous phase containing the dispersed milk serum in readily separable suspension.

6. A process for treating cream to facilitate the separation of milk fat therefrom, comprising In the specifications and claims,

'eficaces milk serum emulsion and to produce -a reversed phase milk serum in milkfat mixture having its Amilk fat and milk serum phases in unstable readily separable relation.

7. A process for treating a owing stream of a dairy product containing milk fat in the dispersed phase and milk serum in the continuous phasev to facilitate the separation of milk fat therefrom, comprising heating the dairy product to at least a ltemperature at which substantially all of the milk fat content is in a melted condition, causing the heated dairy product to iiow into engagement with closely spaced surfaces wherein the relative motion between the heated dairy productand the surfaces is of relatively high velocity, whereby the normal milk fat in milk serum phase of the dairy product emulsion is disrupted and converted to a milk serum suspended in milk fat dairy product mixture having the milk fat and milk serum phases in unstable readily separable relation.

8; A process for treating cream to facilitate the separation therefrom of the milk fat content thereof, comprising heating the cream to at least a milk fat melting temperature, subjecting the cream to milk fat and milk serum phase disruptf ing forces effective to break the normal milk fat in milk serum emulsion and produce a reversed phase mixture of milk fat and milk serum having its milk fat and milk serum portions in unstable readily separable relation.

9. A process for treating cream to produce butter oil therefrom, comprising heating the cream to at least a milk fat melting temperature and breaking the normal milk fat in milk serum phase .relation in the emulsion of said cream to produce 8 l temperature of the adjusted sour cream to a temperature of at least 170 F., and then promptly separating the heated adjusted cream, whereby to break the original cream emulsion and produce a separation fraction containing from to 98 percent milk fat.

l1. A process of treating sour cream in the making of a dairy product containing a' high concentration of milk fat, which comprises adjusting the acidity of the cream to a degree which will enable the eflicient centrifugal separation thereof, raising the temperature of the adjusted sour cream to a temperature of at least F., and then centrifuging the heated cream having the suitably adjusted acidity, whereby to break the original cream emulsion and produce a separation fraction containing from 80 to 98 percent of milk fat.

12. A process for treating a dairy product containing milk fat in the dispersed phase and milk serum in the continuous phase relationship, comprising attempering the dairy product to a temperature at which substantially all of the milk fat content thereof is liquefied and subjecting the dairy product to forces effective to break the normal milk fat in milk serum phase relationship and produce a reverse phase milk serum in milk fat mixture wherein the fat and serum phases are in unstable readily separable relation.

HERMAN C. HORNEMAN. RALPH V. HUSSONG. SIDNEY N. QUAM. BERNARD W. HAMMER.

REFERENCES CITED The following references are of record in the kiile of this patent;

UNITED STATES PATENTS 

